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<table width="100%" summary="page for cuckoos"><tr><td>cuckoos</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Cuckoo Eggs Data</h2>

<h3>Description</h3>

<p>Length and breadth measurements of 120 eggs lain in the nests of six 
different species of host bird.
</p>


<h3>Usage</h3>

<pre>cuckoos</pre>


<h3>Format</h3>

<p>This data frame contains the following columns:
</p>

<dl>
<dt>length</dt><dd><p>the egg lengths in millimeters</p>
</dd>
<dt>breadth</dt><dd><p>the egg breadths in millimeters</p>
</dd>
<dt>species</dt><dd><p>a factor with levels
<code>hedge.sparrow</code>, 
<code>meadow.pipit</code>, 
<code>pied.wagtail</code>, 
<code>robin</code>, 
<code>tree.pipit</code>, 
<code>wren</code> 
</p>
</dd> 
<dt>id</dt><dd><p>a numeric vector</p>
</dd>
</dl>
 


<h3>Source</h3>

<p> Latter, O.H. (1902). The eggs of Cuculus canorus. An
Inquiry into the dimensions of the cuckoo's egg and the relation of the
variations to the size of the eggs of the foster-parent, with notes on
coloration, &amp;c. Biometrika i, 164.  
</p>


<h3>References</h3>

<p>Tippett, L.H.C. 1931: &quot;The Methods of Statistics&quot;. Williams &amp; Norgate, 
London.
</p>


<h3>Examples</h3>

<pre> 
print("Strip and Boxplots - Example 2.1.2")

attach(cuckoos)
oldpar &lt;- par(las = 2) # labels at right angle to axis.
stripchart(length ~ species) 
boxplot(split(cuckoos$length, cuckoos$species),
         xlab="Length of egg", horizontal=TRUE)
detach(cuckoos)
par(oldpar)
pause()

print("Summaries - Example 2.2.2")
sapply(split(cuckoos$length, cuckoos$species), sd)
pause()

print("Example 4.1.4")
wren &lt;- split(cuckoos$length, cuckoos$species)$wren
median(wren)
n &lt;- length(wren)
sqrt(pi/2)*sd(wren)/sqrt(n)  # this s.e. computation assumes normality
</pre>


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